TVC uses derived as singlatable calls

When compiling CMAKE_BUILD_TYPE=Debug WITH_ASAN using clang-7 -O2
the following tests could fail due to insufficient stack size:
main.signal_demo3 sys_vars.max_sp_recursion_depth_func

In commit d30f17af the change of
the loop iteration broke another error handling path that did
"goto error_handling_drop_uncached". Cover this code path with
fault injection, and revert to the correct iteration.

There are two fault injection labels innodb_OOM_prepare_inplace_alter.
Their order was swapped in MDEV-11369, so that the label that used
to be covered in an ADD INDEX code path would become unreachable
because the label that is executed for any ALTER TABLE was executed
first. Let us introduce the label innodb_OOM_prepare_add_index
for the more specific case.

The 10.1 changes to the test case were accidentally omitted
in the merge commit 913e33e4.

The test case was accidentally omitted from the merge
commit 913e33e4.

GCC does not like MY_ATTRIBUTE((nonnull)) on a reference-to-pointer
parameter. clang did not flag an issue wit that.

Rewrite the MDEV-13818 fix to prevent heap-use-after-free.

Add a test case for MDEV-18272.

Part#2 (final): rewritting the code to pass the correct enum_sp_aggregate_type
to the sp_head constructor, so sp_head never changes its aggregation type
later on. The grammar has been simplified and defragmented.
This allowed to check aggregate specific instructions right after
a routine body has been scanned, by calling new LEX methods:
  sp_body_finalize_{procedure|function|trigger|event}()

Moving some C++ code from *.yy to a few new helper methods in LEX.

if create_index_dict() fails, we need to free ctx->add_index[a] too

This fixes innodb.alter_crash and innodb.instant_alter_debug
failures in ASAN_OPTIONS="abort_on_error=1" runs

This fixes main.mysql_client_test, main.mysql_client_test_comp,
main.mysql_client_test_nonblock failures
in ASAN_OPTIONS="abort_on_error=1" runs

row_merge_create_index_graph(): Relay the internal state
from dict_create_index_step(). Our caller should free the index
only if it was not copied, added to the cache, and freed.

row_merge_create_index(): Free the index template if it was
not added to the cache. This is a safer variant of the logic
that was introduced in 65070bef in 10.2.

prepare_inplace_alter_table_dict(): Add additional fault injection
to exercise a code path where we have already added an index
to the cache.

Part#1: moving opt_if_not_exists from "sf_tail" and "sp_tail" to "create".

row_mysql_handle_errors(): Correct the wrong error handling for
the code DB_FOREIGN_EXCEED_MAX_CASCADE that was introduced in

https://github.com/mysql/mysql-server/commit/c0923d396aef46799883390e9dcf7bbf173e4a03

    commit 35f5429e
    Author: Jimmy Yang <jimmy.yang@oracle.com>
    Date:   Wed Oct 6 06:55:34 2010 -0700

        Manual port Bug #Bug #54582 "stack overflow when opening many tables
        linked with foreign keys at once" from mysql-5.1-security to
        mysql-5.5-security again.

        rb://391 approved by Heikki

No known test case exists for repeating the bug before MariaDB 10.2.
The scenario should be that DB_FOREIGN_EXCEED_MAX_CASCADE is returned,
then InnoDB wrongly skips the rollback to the start of the current
row operation, and finally the SQL layer commits the transaction.
Normally the SQL layer would roll back either the entire transaction or
to the start of the statement. In the faulty scenario, InnoDB would
leave the transaction in an inconsistent state, and the SQL layer could
commit the transaction.

using Item_cond

This bug is similar to the bug MDEV-16765.
It appears because of the wrong pushdown into HAVING clause while this
pushdown shouldn't be made at all.
This happens because function that checks if Item_cond can be pushed
always returns that it can be pushed.

To fix it new method Item_cond::excl_dep_on_table() was added.

Call desync_and_pause() and resync_and_resume() only if state is s_synced.

After-merge fix for MDEV-18333 Slow_queries count doesn't increase when slow_query_log is turned off

Do not build range filters with detected impossible WHERE.
Anyway conditions cannot be used anymore to extract ranges for filters.

Right argument of Item_in_optimizer can not be cast to Item_in_subselect in invisible mode.

This fixes main.mysql_client_test, main.mysql_client_test_comp,
main.mysql_client_test_nonblock failures
in ASAN_OPTIONS="abort_on_error=1" runs

don't initialize mysql structure before it actually becomes needed.

This fixes main.mysqladmin failures
in ASAN_OPTIONS="abort_on_error=1" runs

free already allocated indexes if row_merge_create_index() fails

This fixes innodb.alter_crash failure
in ASAN_OPTIONS="abort_on_error=1" runs

use the correct delete operator

This fixes mroonga/storage.column_generated_stored_add_column failures
in ASAN_OPTIONS="abort_on_error=1" runs

MDEV-18625 ASAN unknown-crash in my_copy_fix_mb / ha_mroonga::storage_inplace_alter_table_add_column

disable inplace alter for adding stored generated columns.

This fixes mroonga/storage.column_generated_stored_add_column failures
in ASAN_OPTIONS="abort_on_error=1" runs

Also, add a test case that shows the bug without ASAN.

fixes these test failures in ASAN builds (in 10.1 and 10.4):
* main.signal_demo3
* main.sp
* sys_vars.max_sp_recursion_depth_func
* mroonga/storage.foreign_key_delete_existent
* mroonga/storage.foreign_key_delete_nonexistent
* mroonga/storage.foreign_key_insert_existent
* mroonga/storage.foreign_key_update_existent
* mroonga/storage.foreign_key_update_nonexistent
* mroonga/storage.function_command_auto-escape
* mroonga/storage.function_command_select
* mroonga/storage.variable_enable_operations_recording_insert

thd->lex->m_sql_cmd was not cleared between queries.
log_slow_query() could crash (when running mtr --ps) because of this.